The importance of small ruminants in the tropics in general is well recognised (Williamson and Payne, 1978). Small ruminants are
reared mainly for four functions, namely: (1) Meat, (2) milk,(3) skin and (4) wool, according
to order of importance. According to the FAO (1982)
tropical Africa has about one-sixth and about a
third of the total world flock of sheep and goats, respectively. Total meat produced from small ruminants in Africa was 1.3 million metric tonnes (about 16%
of the world total from sheep and goats). Within Africa, sheep and goats contributed 10.9% and 8.4%, respectively, of our
total meat. Total meat from African sheep and goats
contributed 12.0%, respectively, of the world total meat production from these two species. Sheep and goats in
Africa produced 8.6% and 18.2% respectively, of the
world total amount of milk produced from these two species and the production from both accounted for 13.6% of milk collected from small ruminants in the world. According to Wilson (1982),
sheep and goats accounted for 17% of the total ruminant
biomass in Africa. Table 1 shows the population of
sheep and goats in Africa and the amount of meat and milk produced from them as
compared with world figures.

DISTRIBUTION, OWNERSHIP AND FLOCK SIZE

The
distribution of sheep and goats in Africa is not even and numbers tend to be higher in the drier areas. Consequently, flock sizes
are larger in the drier than in the humid areas.
Thus, in some areas (e.g. in West Africa) flock sizes
decrease from north to south (ILCA, 1979; Otchere et al. 1985). In East Africa (e.g. Ethiopia and Kenya) flocks are smaller in the highlands
compared with the lowlands (Wilson, 1982). Flock sizes are
generally larger in the pastoral and smaller in the humid agricultural regions
(ILCA, 1979; Bayer, 1984). Tables 2–4 show the
general pattern of ownership and flock sizes in arable, pastoral and agro-pastoral societies in Nigeria, Kenya Tchad, and Mali. The data suggests that the pattern of ownership of small stock in Africa is rather
varied and extremely complex. The majority of small ruminants is owned by
individuals or families in rural areas and the number per group is small. Small
stock nevertheless form an integral part of
the farming system (Wilson).

Van
Vlaenderen (1985) described sheep and goat husbandry in Togo as being casual rather than an organised activity for the
following reasons: (a) animals have no benefit of prophylactic
or curative medicinal treatment: (b) littre or no supplementary feed is offerred; (c) no good flock management is
practised; (d) poor housing (e) tethering of animals
during the planting season so as to avoid crop damage.
The above criticism will seem to apply to small ruminant production in traditional systems throughout tropical Africa. According
to Wilson (1982), however, Africans who keep small stock
rarely do so for irrational reasons and that such reasons are perfectly in
keeping with the problems encounterred and the specific objectives of the owners. Table 5 shows that there appears
to be a similarity of sheep or goat flock structures
in the traditional system of small ruminant production across different zones of tropical Africa.

Small
ruminants are widely distributed and are of great importance as a major
source of livelihood of the small farmer and the landless in rural communities in tropical Africa. Indications, however,
are that the productivity of small ruminants in this system is low and that
there is ample opportunity for improvement.

Age
at first parturition, parturition interval and litter size determine lifetime production as well as efficiency of production.
Genetic improvement and or efficiency of production can
be more easily ameliorated in small ruminants because
they have a faster population turnover rate. Such progress would be achieved if increased selection pressure is effectively
applied. Several of these production parameters can be
improved because they are under the influence of environmental and ecological factors. Available data
suggest that reproductive efficiency of small ruminants
in tropical Africa is reasonably high and hence fertility would not be
recommended for any improvement unless present nutritional, health and
management constraints are removed.

Of paramount importance
to economic productivity and reproductive efficiency in small ruminants is mortality. Both pre-weaning and post-weaning
mortality of small ruminants in tropical Africa is very high (Table 6). Several factors have been reported to affect mortality in small stock
in various areas in tropical Africa.
Among these are season and type of birth (Peacock, 1982), length of the previous parturition interval (Wilson, 1981), parturition
number (Fall et al., 1982) and disease (Mack, 1982). All of these
effects are clearly related to nutrition, health and management.

GENERAL MANAGEMENT AND NUTRITION

Small
ruminant production in Africa is not developed. The fact that holdings are
small seem not to give owners incentives for improved husbandry practices. In wetter
areas, where arable cropping is the practice, small stock are tethered during the cropping season in an attempt to prevent
crop damage (Okello and Obwolo, 1985;
Adua and Ngere, 1979).

In
Northern Nigeria, Adu and Ngere (1979) described a compound system practised
by Hausas who are settled and therefore keep their small stock tethered in their compounds and feed them soilage in the rainy season.
Otchere et al., (1985) reported that pastoralist
Fulani in Giwa district of northern Nigeria allow sheep to accompany cattle for grazing but tethered their goats
under shelter. These goats were fed cut-and-carry green forage in the rainy
season. Similar management systems have been described by
Wilson (1982, 1985). The general concensus is that, after
crops have been harvested, small stock are let loose to feed on crop residues and fend for themselves. According to van
Vlaenderen (1985) adult animals lost 22% of their body weight while average daily gain in lambs was 30% lower
during the cropping season which
spanned April to November in northern Togo. This observation is true in most heavily cropped areas and
indicates that all is not well with the nutrition of small stock in
these areas during the rainy season though undernutrition during the dry season had often been stressed as a limiting factor
in ruminant production in tropical
Africa (Otchere et al., 1977;
ILCA, 1979; Meyn, 1980).

Improved
animal nutrition appears to be a more critical factor in increasing small stock productivity. Native rangelands provide the
cheapest source of nutrients for ruminants. It is however an accepted fact
that for a greater part of the year, grasslands in the tropics do not supply
sufficient nutrients to stock for greater
productivity. Otchere et al., (1977) reported that West
African Dwarf sheep, on the Accra Plains of Ghana, which received no
supplementary feed during the dry season (December to
February) lost about 15% of their body weight. Two groups of animals after the days normal grazing, got
supplements made up of dried cassava peels and rice straw, respectively, each
fortified with urea and molasses. Those
which received rice straw lost 2g per head per head per day while the cassava
peels group gained 19g per head per day and the control group lost 19g per head per day. That supplementation of grazing
enhances growth rate had also been reported
by van Vlaenderen (1985) and Kolff and Wilson (1985). Thus, the need for supplementation
of natural forage with agro-industrial by-products cannot be overemphasized. The use of conventional by-products (e.g. oil
cakes and milling byproducts)
is severely limited by availability and high cost. In some instances by-products,
like gagasse and molasses, have had alternative uses (fuel or alcohol
distillation) rather than for stock feeding.

Many crop discards like cocoa husks and corn cobs have not found
their way into stock feeding even though they have been shown to be potentially
useful (Adeyanju et al.,1975;
Otchere et al.,1983). Many of these crop discards are not
used because production is by small scale farmers scattered over a wide
area thereby making collection impractable.
It must be mentioned however that there are several large plantations
and or farms now in Africa on which such crop discards are allowed to rot. Such large scale farms could include fattening
of small stock in their operations so as to utilise these discards.

There are at least three breweries in most tropical African countries (Nigeria has about twenty). Several tonnes of spent brewer's grains
are wasted because only a few of the breweries have drying facilities. It is
suggested that future breweries be required to include
drying facilities so as to facilitate the use of the dried brewer's grains for stock feeding. Efficient use of
such by-products for stock feeding under present
conditions would call for the stratification of the system of small ruminant production. Estimates by ILCA
(1979) showed that Africa potentially had agro-industrial
by-products that could be used for fattening about one million small ruminants for a 90 day period each year during the
1980s.

Several factors make it difficult for Africa's agro-industrial by-products to be
harnessed. In the mean time, wholesale rangeland improvement is not practicable
because grazing land is communal. The majortiy of stock owners do not own land
and for those who have, the farm sizes are small and grossly subsistence
crop-based. An integration of forage legumes into the
cropping system of small stock owners would go a long way to improve the
productivity of their animals. Research along these
lines has been initiated by ILCA in Nigeria and Mali (ILCA 1982) and the Small
Ruminant Collaborative Research Support Programme (SR-CRSP) of the United States Agency for International Development in Kenya
(SR-CRSP, 1982). Initial indicators appear very favourable,
and it is therefore suggested more such experiments need to be conducted in
other zones in several countries. National research institutes
(both crop and livestock) should cooperate and find feasible avenues for integrating livestock and crop production. A
systems approach would appear to yield
relevant results and research efforts should emphasise the idenfification of
factors which, when modified or eliminated, will enable small ruminant
producers in tropical Africa to have control over the productivity of their animals
and not under the control of ecology as is the case at the present.

ANIMAL HEALTH

Helminthiasis
and ectoparasitosis are widespread in tropical Africa and both seriously affect the productivity of small ruminants.
Helminthiasis is a serious problem towards the end of the rainy season while
ectoparasitosis inflicts heavy damage during the rains to early dry season. Van
Vlaenderen (1985) reported that deworming of adult sheep in Togo did not have
any effect on weight gain or mortality. In lambs, however, deworming reduced
mortality by 50% but growth was not affected.
In ILCA studies in south west Nigeria, Opasina (1984) reported that
ectoparasitic control in goats appeared not to result in
higher growth rates.

The author has observed a condition of
“lameness” in small ruminants which strikes normally at the beginning of the rainly season in
norther Nigeria. Affected animals have impaired locomotion and their condition
normally worsens if not controlled. Surgical
intervention had invariably shown that there was an in-vagination of hairs
which had formed into a cylindrical shape interdigitally. If removed and
treated with tincture of iodine the animal recovered within a short time.

In West Africa, peste de petit ruminants (PPR) is
endemic. Studies bu ILCA scientist
in south west Nigeria (Mack, 1982) showed that dipping with gammatox against ectoparasites and annual vaccination against PPR
very dramatically reduced mortality
and increased small stock numbers in village flocks. It was observed that
mortality among sheep and goats in the ILCA studies decreased by 75%. While death rate was reduced, offtake rate did not increase
and, therefore, flock inventories
rose. Cost benefit analysis demonstrated that annual vaccination against PPR was viable under south west Nigeria conditions. It is
suggested that the vaccination programme would be
even more viable in the pastoral and agro-pastoral regions of West Africa where holdings are larger and that
it can be a part of the annual vaccinations against
rinderpest in cattle.

An efficient, well-planned animal health service is a
pre-requisite for increasing small ruminant
production in tropical Africa. It must be stressed, however, that any improvement in animal health services must
go hand in hand with an adequate improvement in the provision of feed. If this
is not done, expected improvements in productivity may
not be realised and could lead to further destruction of rangelands in major producing areas as a result of large increase in
numbers. An improvement in the
performance of small ruminants in tropical Africa would directly improve the diet and standard of living
of the large number of rural smallholders.